SS-Offshore Offloading Systems and Operations Bonded Flexible Oil Offloading Lines, A Cost Effective Alternative to Traditional Oil Offloading Lines

Abstract

In deepwater offshore fields where spread moored FPSOs are involved, theproduced oil is generally offloaded to shuttle tankers via Oil Offloading Lines(OOLs) connected between the FPSO and deepwater buoy. Until recently, two typesof Oil Offloading Lines (OOL) were used for the transfer of stabilized crudeoil between the FPSO and the offloading buoy: steel pipe or unbonded flexiblepipe. Since 2000 Trelleborg and SBM have been working on an alternativeoffloading solution made of bonded flexible hoses called TRELLINE™ (seereference [1]). This product can be adapted to a large range of applicationslike for the offloading of oil from a MOPUstor to a submerged loading system(SLS). In September 2005, the TRELLINE™ was used for OOL for the first time for SNEPCOwho decided to supplement the existing Bonga OOL system with one 20" IDTRELLINE™ to match with ultra short delivery. In December 2006, the OOL wasinstalled with the SBM vessel Dynamic Installer (see reference [2]). In July 2008, Total Exploration Production Angola (TEPA) decided to use theTRELLINE™ for the 18" ID OOLs of the Pazflor field. For Pazflor, the producedoil is exported from the FPSO to the buoy located 1,856m away, via twoidentical 18" OOLs of 2,070 m long, made of 175 hoses sections each. The OOLsare connected to the FPSO and the buoy by the means of gimbal tables thatdecouple the tension and bending loading. Specificity of Pazflor Trelline hoseswas their hig desing pressure equal to 50 bars that had required intensivequalification and testing program, and making Pazflor export lines a" world-first". Based on past installation experiences on Bonga project (OOL) for SNEPCO in2006 and on Yme project (SLS) for Talisman Energy Norge in 2008, see reference[3]), a new installation method has been developed. A specifically designedpatented equipment was developed to ensure a safe and quick offshoreinstallation. It comprises:An A-Frame designed to upend individual hose from deck to the fireline.An assembly platform designed for vertical assembly of the hoses.A large deployment wheel ensuring the transition from vertical to horizontalof the OOL at the sea surface. In June 2011, the SBM vessel Normand Installer successfully installed the twoPazflor OOLs. The two OOLs were assembled and hooked up in less than 4 weeks(mobilizations included). The TRELLINE™ OOL system demonstrated its advantages in term of design, procurement cost, lead time, installation efficiency and operationaladvantages. It will further demonstrate maintenance advantages.

Mathematical Modelling of Bonded Marine Hoses for Single Point Mooring (SPM) Systems, with Catenary Anchor Leg Mooring (CALM) Buoy Application—A Review

“…There are three categories of SPM moorings that will be looked: SPMs, CALM buoys and marine hose systems. These are based on their operational relevance to the CALM buoy system or the connecting FPSO tanker in an SPM unloading or discharging hose system, like deepwater lines, Oil Offloading Lines (OLLs), flexible riser pipes, flexible hoses, and other CALM buoy hose systems [145][146][147][148][149][150][151][152][153][154]. To avoid failure, safety must be key for installation and (un)loading [155][156][157].…”

An Overview on Bonded Marine Hoses for Sustainable Fluid Transfer and (Un)Loading Operations via Floating Offshore Structures (FOS)

“…In addition, the FPSO's fixed position and the tandem mooring with the shuttle tanker make it quite challenging to achieve. Typical materials for such deepwater export lines have been reported by Trelleborg [89][90][91][92][93]. A deepwater export connection to a CALM buoy, where the shuttle tanker moors, could be one possibility [91][92][93], as in Figure 16.…”

“…Typical materials for such deepwater export lines have been reported by Trelleborg [89][90][91][92][93]. A deepwater export connection to a CALM buoy, where the shuttle tanker moors, could be one possibility [91][92][93], as in Figure 16. The tankers may weathervane here without having to worry about colliding with the FPSO.…”

“…In addition, the FPSO's fixed position and the tandem mooring with the shuttle tanker make it quite challenging to achieve. Typical materials for such deepwater export lines have been reported by Trelleborg [89][90][91][92][93]…”

“…In addition, the FPSO's fixed position and the tandem mooring with the shuttle tanker make it quite challenging to achieve. Typical materials for such deepwater export lines have been reported by Trelleborg [89][90][91][92][93] bility [91][92][93], as in Figure 16. The tankers may weathervane here without having to worry about colliding with the FPSO.…”